The brain is inundated with a continuous flow of information arising from exogenous and endogenous sources, necessitating control mechanisms to identify, and in turn act upon, the currently most salient stimuli. A distinct network, composed of insula and ACC nodes, has been suggested to play a critical and causal role in the initiation, maintenance, and adjustment of attentional control (Bressler and Menon 2010; Menon and Uddin 2010; Dosenbach et al., 2006, 2007, 2008). Such findings suggest the fractionation of the TPN discussed above into at least two dissociable sub-networks. Indeed, in the absence of explicit task demands, two distinct networks appear to exist, each subserving different psychological processes: one anchored in anterior insula and ACC termed the “salience network” (SN), and a second composed of lateral prefrontal and parietal regions termed the “executive control network” (ECN; Seeley et al., 2007).
